The invention is directed to a wireless or non-contact power transfer device for charging mobile/portable devices and a wireless mobile/portable device charging system.
Wireless power transfer systems are available for charging mobile phone and other portable devices; however, there are limitations with respect to the known arrangements. For instance, in one known non-contact power transfer device used in connection with mobile phones, the device to be charged is placed in a cradle having a power transfer coil located at the base of the cradle and a power receiving coil located in the device to be charged. The cradle holds the device in a fixed position so that the power transmission coil as well as the power receiving coil are aligned with one another. This arrangement does not allow for universal use as the cradle is specifically adapted to the geometry of the particular mobile phone.
In another known wireless charging system for a portable electronic device, multiple different coil arrangements are provided on a flat side of a cradle. This is disclosed as allowing different devices to be positioned such that at least one of the primary induction coils in the power supply cradle is generally aligned with a receiving coil in a device to be charged. This arrangement however does not provide for efficient power transfer depending upon whether or not a device to be charged is placed in close proximity to one of the multiple coils provided in the charging station.
In another known device, a docking station is provided for inductive charging of a portable electronic device. However, in order to allow the device to be charged in multiple different positions, the docking station is configured to mechanically hold the device in one of several positions so that the induction coil in the docking station aligns with the receiving coil in the device to be charged.
Other charging systems require the alignment and insertion of a specific charging connector or contact between exposed conductors of a charging cradle with exposed conductors in the device to be charged.
In addition to the issues noted above, none of the known non-contact or wireless power transfer devices are inherently suitable to the geometry typical of tablet-type computing devices due to the thickness of the tablet and/or required power receiver.